[Iv]

Well, if we exclude all the visual spectrum, which is the most useful part of the RF spectrum for animals: transparent to water and atmosphere, reflects well on a lot of surfaces, has kilometers of range if there is line-of-sight, wavelength of a size making it possible to have lens and sensor cells small enough to fit an animal.

But yes, the idea is that if there were a physical principle that would be super useful to animals yet not witnessed in nature, that is something that needs to be explained. There are reasons for evolution to miss a solution.

In the case of quantum computing, I could not really see it: the effects happen at a scale where evolution operates, and could easily be integrated, e.g. in nerve cells to create a workable signal. I thought reasonable to make it an element to feed my skepticism, though not a ultimately strong argument to deny any possibility of quantum computing.

[TheOtherHobbes]

Evolution is a relatively poor search algorithm that tends to get stuck at local maxima. Unlike science, it doesn't build maps and models for exploration and extrapolation.

So far as I know there's no general theory of theories which quantifies this, so there's no way to make predictions about the cut-off point for evolutionary invention.

But in a hand-wavy way, evolution's only feedback loop is first-order and binary - mutate and reproduce at a positive replacement rate, or not.

The feedback loop in science is more complex. Instead of being driven by a random search, "mutations" are guided by a creative model. This creates momentum in the model space which isn't available to evolution - which in turn makes it possible to discover more complex and less immediately accessible solutions.

It also makes it possible to build systems whose value is guaranteed, or at least strongly suspected, before resources are diverted to making them physical.

The bottom line is evolution is only ever going to find a small subset of all possible biological configurations, and that space is going to exclude many features that are available to science-driven search.

(Of course you can argue that scientific meta-search was a product of evolution anyway, so the distinction is academic.)

[josalhor]

The properties of quantum computing require incredible low temperatures. We are talking close to 0 K, not -few degrees. That is unfeasible for nature to develop naturally as the advantages of using a quantum algorithm would be far lower than the natural disadvantages of energy requirements, weight, natural complexity, lack of versatility... On top of all that, quantum computing and algorithms always require some kind of non quantum processing, so on top of that we would include non quantum processing...

[xenadu02]

You seem to be engaging in a "No True Scotsman" argument here.

I could point to MRIs and SQUID, but I guess you could claim some animals sense magnetism (for wayfinding or determining north). I don't consider those to be in the same league but then we're back to arguing semantics under your definitions.

The fact remains that physical phenomena exist that evolution did not discover. There are perfectly good reasons for that, but I don't think it is fair to say if nature doesn't use it then it is "questionable".

[knzhou]

What's the explanation for why living things don't contain superconductors?

Of course: you need an extremely cold and clean environment, which is very hard to generate in a cell. And it wouldn't even be that useful for cells anyway.

The exact same reasoning applies to quantum computers.